The risk of property damage or a lawsuit from a dog bite is too high. 

The payments and interest are high.

Taxes : Taxes have been a brewing crisis nationwide for sometime, Chicago is another prime example of a major municipality struggling under high debt load.

We specialize in helping investors access opportunities in both residential and commercial markets, leveraging our network and industry knowledge to identify high-potential deals.

Also in many areas prices are very high.

Highly doubtful that there is a NNN lease equivilatent for residential properties.

Here are some indicators to help you assess a buyer's seriousness:Questions: Serious buyers will ask detailed questions about the property, such as maintenance costs, neighborhood amenities, and property taxesStrong Offer: If a buyer makes a strong offer quickly, it often indicates a high level of interest and intent to purchasePrivate Buyers: If approached by a private buyer, ensure they provide a Letter of Intent (LOI) and proof of funds.  

And therein lies the risk of high-leverage.  

Jobs are always a good indicator of growth areas especially good high paying jobs.

Be sure your lender is comfortable with this, as many fear giving folks primary loans for properties they view as having a high probability of being turned into a purely investment.